This Standard defines requirements for the performance of Fault Tree Analysis (FTA) on space projects and incorporates the IEC 61025 standard into the ECSS system.With effect from the date of approval, this Standard announces the adoption of the external document on a restricted basis for use in the European Cooperation for Space Standardization (ECSS) system.This standard may be tailored for the specific characteristic and constraints of a space project in conformance with ECSS-S-ST-00.